#312B9B
Closest named color: Sapphire (#2138AB). oklch(37.8% 0.174 276.5), rgb(49, 43, 155).
Aa
White text reads best on this color (10.77:1).
About this color
#312B9B is a dark, vivid blue. In OKLCH its lightness is 38%, its chroma 0.174 and its hue 276°. Its hue sits on the cool side of the wheel. The nearest named color is Sapphire (#2138AB), ΔE 0.041 away. White text reads best on it, at 10.77:1.
| Hue family | Blues |
| Lightness | dark (38%) |
| Chroma | vivid (0.174) |
| Temperature | cool |
| Nearest name | Sapphire (#2138AB) |
| Black text | 1.94:1 |
| White text | 10.77:1 |
Values
| HEX | #312B9B |
| RGB | rgb(49, 43, 155) |
| HSL | hsl(243, 57%, 39%) |
| OKLCH | oklch(37.8% 0.174 276.5) |
Contrast
WCAG 2 contrast ratios are the conformance target: AA needs 4.5:1 for body text and 3:1 for large text, AAA needs 7:1. APCA Lc values are supplementary guidance from the WCAG 3 drafts.
| Pair | WCAG 2 | Result | APCA | APCA guidance |
|---|---|---|---|---|
| White text on #312B9B | 10.77:1 | AAA | Lc -98.2 | Preferred for body text |
| Black text on #312B9B | 1.94:1 | Fails | Lc 9.7 | Not readable |
| #312B9B text on white | 10.77:1 | AAA | Lc 94.2 | Preferred for body text |
| #312B9B text on black | 1.94:1 | Fails | Lc -8.4 | Not readable |
Tints and shades
A 50–950 scale built in OKLCH: the hue is held, lightness follows a Tailwind v4-like curve, and every step is kept inside the sRGB gamut. This color sits at step 900.
-
Step 50
50
#F3F5FF
oklch(97.2% 0.013 277.1)
-
Step 100
100
#E4E9FF
oklch(93.7% 0.03 275.6)
-
Step 200
200
#CFD7FF
oklch(88.6% 0.056 276.3)
-
Step 300
300
#B0BBFF
oklch(80.8% 0.097 276.9)
-
Step 400
400
#8895FF
oklch(70.6% 0.155 276.4)
-
Step 500
500
#6E76FF
oklch(63.1% 0.2 276.5)
-
Step 600
600
#5851FF
oklch(55.6% 0.248 276.5)
-
Step 700
700
#4A2CF4
oklch(49.1% 0.27 276.5)
-
Step 800
800
#3B29C4
oklch(42.6% 0.223 276.4)
-
Step 900
900 (this color)
#312B9B
oklch(37.8% 0.174 276.5)
-
Step 950
950
#1C1B5A
oklch(27% 0.11 276.8)
#312B9B with color blindness
Simulated with the Machado et al. (2009) model. ΔE is how far the color moves: below about 0.02 you would not notice a change.
| Vision | Seen as | Shift (ΔE) |
|---|---|---|
| Protanopia (no red cones) | #00429E | 0.058 |
| Deuteranopia (no green cones) | #003999 | 0.047 |
| Tritanopia (no blue cones) | #004A60 | 0.140 |
| Achromatopsia (no color) | #3E3E3E | 0.175 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #312B9B
#312B9B
oklch(37.8% 0.174 276.5)
- #4E4100
#4E4100
oklch(37.8% 0.078 96.2)
Analogous
Neighbouring hues, 30° either side.
Split complementary
The two hues beside the complement (150° and 210°).
Triadic
Three hues spaced 120° apart.
Palettes with this color
Curated palettes that contain a color within ΔE 0.04 (OKLab) of #312B9B, closest first.
No curated palette has a color within ΔE 0.04 of #312B9B.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Sapphire #2138AB ΔE 0.041
- Indigo Blue #3A18B1 ΔE 0.043
- Imperial Purple #480CA8 ΔE 0.054
- Blueberry #464196 ΔE 0.065
- Ultramarine #2000B1 ΔE 0.065
- Dark Slate Blue #483D8B ΔE 0.066
- Royal #0C1793 ΔE 0.067
- Cobalt #1E488F ΔE 0.072
Use #312B9B in your product
Turn it into light and dark UI roles checked for contrast, then export to Tailwind v4, shadcn/ui, CSS or design tokens.